Screw-driver.



G. P. BGUTL'ER. SCREW DRIVER.

'APPLIOLTiON FILED SEPT. 25, 1906.

PATENTED DEG. 25', 1906. Y

. UNITED STATES PATENT oEEIo GEORGE P. BUTLER, OF NEW HAVEN,ooNNEor1our.

SC W-DRIVER] Haven, in the county of New Haven and State of Connecticut,have invented certain new and useful Improvements in Screw- Drivers, ofwhich the following is aspecifica- 'tion, reference being had therein tothe accompanying drawings.

My lnventlon relates to new and useful 1mprovements 1n screw-drlvers,and has for its object, among other things, the construction of ascrew-driver which will engage the slot in a screw-head and be heldtherein, so as to prevent its accidental disengagement therefrom, and toreinforce and strengthen that portion of the screw-driver which is doingthe work and in contact with the screw-head, and thereby produce a toolthat is practically indestructible.

To these and other ends my invention consists in the screw-driver havingthe details of construction hereinafter described, and more particularlypointed out in the claims. 4

Referring to the drawings, in which like numerals of reference designatelike parts in g the several figures, Figure 1 is an elevation of myimproved screw-driver looking toward one of its sides. Fig. 2 is asimilar elevation looking at another side. Fig. 3 is an end elevationlooking toward the right of Fig. 1; and Fig. 4 is amodification of myinvention, illustrating how the screw-driver may be adapted for use intheordinary brace.

Practice has demonstrated that the head of a screw-driver of theordinary type frequently slips out of the slot in the screw-' head,-more especially as the screw is making its last turns when being drivenin or starting the screw in taking it out, particularly if the slot hasbecome worn or if the wood is hard. This action not only injures andmars the screw-head, but frequently the wood also,

' aside from destroying the head of the screwdriver by turning ortwisting the end thereof.

It is to overcome these and other objections to the present type ofscrew-driver that I have designed the screw-driver about to bedescribed. I

Referring to the drawings, the'numeral 1 designates the body of ascrew-driver, which terminates at its end in a head that is providedwith teeth 2 and 3. These teeth are upon oppositesides of the head,being substantially one-half of the width thereof. The front face 4 ofeach tooth is undercut, as

Specification of Letters Patent.

Application filed fieptember 25. 1905. serial No. 280.039-

Patented. Dec. 25, 19.

shown in Fig. 2, and the rear face 5 is beveled-sharply to give-themaximum strength to the tooth and makea powerful drive upon thescrew-head. A small notch 6 is cut in each of the faces 5 to-facilit'atetheen'trance of the screw-driver into the slot of roundhead screws.

By reason, of the undercut face 4 the teeth engage the walls of the slotin the screw-head near the bottom thereof, where the head-is strongestand least liable, to injury, and also hold the screw-driver fromslipping out of the slot. Apraotical demonstration of the use of myinvention has shown that it is almost impossible to accidentallydisengage the screw-driver from the screw-head; but, on the contrary,the more powerful the drive the tighterthe hold.

In Figs. 1 and 2 I have illustrated the screw-driver with a toothed headat each end, one of which is used for driving screws in and the otherfor driving them out.

the exact construction herein shown and de-.

scribed, but claim all that falls fairly within the spirit and scope ofmy invention.

, Having described my invention, what I claim as new is' f 1. As animproved article of manufacture, a screw-driver having a head portionprovided with oppositely-disposed slot-engaging teeth of less width thansaid head, each of said teeth having an undercut front face, asubstantially flat end face, and a beveled face opposite to-saidfrontface and terminating at the edge of said end face.

2. As an improved article of manufacture, a screw-driver having a headportion provided with oppositely-disposed slot-engaging teeth of lesswidth than said head, each of said teeth having an undercut front face,a substantially flat end face, and a beveled face opposite to said frontface and terminating at the edge of said end face, the line forming thejunction of the front face of said teeth with the end face thereof beingon the same line as the junction of the'beveled face of the adjoiningtooth with said end face.

3. Asan improved article of manufacture,

I face opposite to saidfront face and terminat- .,thereof parallel witheach ing at the edge of'said end face, the line forming the unction 'ofthe front face of said teeth with the end face thereof being on the sameline as the junction of the beveled face of the adjoining teeth withsaid end face, said end faces being of uniform width, the side edgesother and one end face forming acontinuation of the adjoining end face.

4. As an improved article of manufacture, a screwdriver having a headportion provided with slot-engaging teeth of less width than said head,each of said teeth having an undercut front face and a beveled rear facesaid beveled face being notched adjacent td its inner edge.

5. In an improved article of manufacture, a screw-driver having a body 1terminating at one end in a head portion, constructc with slot-engagingteeth 2 and 3 said teeth being upon opposite sides of said head portionand having an undercut face 4E-upon one side of the center thereof and abeveled face 5 upon the opposite side thereof, said beveled face beingprovided with a notch 6.

In testimony whereof I aflix mysignature in presence of two witnesses.

GEORGE P. BUTLER.

